Surface Of Implants Research Articles

Influence of the Sodium Titanate Crystal Size of Biomimetic Dental Implants on Osteoblastic Behavior: An In Vitro Study

Treating the surfaces of dental implants in an alkaline medium allows us to obtain microstructures of sodium titanate crystals that favor the appearance of apatite in the physiological environment, producing osteoconductive surfaces. In this research, 385 discs made of titanium used in dental implants underwent different NaOH treatments with a 6M concentration at 600 °C and cooling rates of 20, 50, 75, and 115 °C/h. Using high-resolution electron microscopy, the microstructures were observed, and the different crystal sizes were determined and compared with control samples (those without biomimetic treatment). Roughness, wettability, surface energy and the sodium content of the surface were determined. The different surfaces were cultured with human osteoblastic cells; cell adhesion was determined at 3 and 14 days, and the degree of mineralization was determined at 14 days via alkaline phosphatase levels. Variations in the microstructure and size of sodium titanate crystals in NaOH solutions rich (1 g/L) or low in calcium (approximately 100 ppm) were determined. The results show that as the cooling rate increases, the size of the crystals decreases (from 0.4 μm to 0.8 μm) except for the case of 115 °C/h, when the rate is too fast for crystalline nucleation to occur on the surface of the titanium. The thermochemical treatment does not influence the roughness or the cooling rate since a Sa of 0.21 μm is maintained. However, the presence of titanate causes a decrease in the contact angle from 70° to 42° and, in turn, causes an increase in the total surface energy from 35 to 49.5 mJ/m2, with the polar component standing out in this energy increase. No variations were observed in the thermochemical treatments in the presence of sodium, which was around 1200 ppm. It was observed that as the size of the crystals decreases, cell adhesion increases at 3 days and decreases at 14 days. This is because finer crystals on the surface are already in the mineralization process, as demonstrated using the level of alkaline phosphatase that is maximal for the cooling rate of 75 °C/h. It was possible to confirm that the variations in the concentrated NaOH solutions with different calcium contents did not affect the crystal sizes or the microstructure of the surface. This research makes it possible to obtain dental implants with different mineralization speeds depending on the cooling rate applied.

A systematic assessment of the stability of SLA® vs. SLActive® implant surfaces over 12 weeks.

This study aims to assess the impact of two implant surfaces, SLA and SLActive, on implant stability, measured by ISQ levels over a 12-week period. A comprehensive search of MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Dentistry and Oral Sciences databases for randomized controlled trials (RCTs) up to February 2023 was conducted. The inclusion criteria were studies involving adult patients treated with SLA and SLActive implants, with assessment of implant stability through ISQ levels up to 12 weeks post-placement. From the initial 180 potentially eligible publications identified, six RCTs were included in our analysis, comprising 326 implants (50.6% SLA and 49.4% SLActive). Three studies were classified as low risk, while three had an unclear risk of bias. Overall, SLActive implants demonstrated comparable stability levels, as measured by ISQ, to SLA implants within the 12-week interval for implants placed in the maxillary or mandibular region. However, findings from the RCTs suggest that the SLActive surface led to an earlier transition point, a faster return to stability levels, and higher ISQ values at the end of 12 weeks compared to the SLA surface for implants placed in the palatal region. SLActive surfaces exhibited stability levels similar to SLA surfaces for maxillary and mandibular implants. Notably, for palatal implants, SLActive resulted in a quicker transition point and higher stability levels at the 12-week mark. Due to the limited number of trials and potential study heterogeneity, further research is needed to validate these findings.

Long-Term Clinical Study on Sandblasted-Acid-Etched Surface Dental Implants: 12-Year Follow-Up.

Sandblasting and acid etching are common procedures used to treat implant surfaces, enhancing osseointegration and improving clinical success rates. This clinical study aimed to evaluate the long-term outcomes of sandblasted and acid-etched implants. A total of 303 implants were placed in 114 partially and totally edentulous patients using a two-stage surgical technique and an early loading protocol (6-8 weeks). Clinical findings for implants and prosthetics were evaluated over a 12-year follow-up period. A total of 12 implants (3.9%) failed, with 3 failures occurring during the healing period before loading and 9 due to peri-implantitis. The cumulative survival rate for all implants was 96.1%. A total of 156 prostheses were placed on 300 implants, 87 single crowns, 45 partial fixed bridges, 9 full-arch fixed restorations, and 15 overdentures. The mean marginal bone loss was 1.18 mm. (SD. 0.64 mm.). Thirty-nine implants (13%) in twenty-four patients exhibited peri-implantitis. Technical complications, including prosthetic screw loosening or fracture, ceramic chipping, and acrylic fractures, were observed in 24 subjects (21.1%). Sandblasted and acid-etched surface implants placed in the maxilla and mandible reported favorable outcomes and stable tissue conditions with an early loading protocol.

Osteon-mimetic Laser-structured Ti-6Al-4V Supports for Guided Stem Cell Growth

Implant surfaces play an important role in determining cell responses, including attachment, proliferation, migration, and differentiation. With rapid developments in micro-and nano-fabrication methods, precisely controlled patterns can be generated on implant surfaces. Osteon-mimetic structures are of great interest as new surface designs of bone implants for creating conditions of natural bone tissue growth. In this work, we used laser ablation technique to create a biomimetic relief on Ti-6Al-4V supports. The basis of the relief is patterns of micrometer concentric lamellae-like rings of different widths and periodicities. A distinctive feature of these reliefs is the presence of a highly porous nanocoating of titanium alloy component oxides, formed as a result of reverse deposition from the vapor-gas phase during ablation. Our investigation on human mesenchymal stem cells revealed that the osteon-mimetic microreliefs’ topography significantly influenced their adhesion, proliferation, and polarization. However, the presence of the nanocoating further impacted these cells by altering the number and localization of their focal contacts. The outcomes of this work demonstrate an innovative direction towards the design of osteon-mimetic topographies on implantable materials. This work also holds the potential to identify optimal combinations of microrelief and nanocoating parameters to elicit specific cellular responses.

Photoelectron Therapy Preventing the Formation of Bacterial Biofilm on Titanium Implants.

The exogenous bacterial infection and formation of biofilm on the surface of titanium implants can affect the adhesion, proliferation, and differentiation of cells associated with osteogenesis, ultimately leading to surgical failure. This study focuses on two critical stages for biofilm formation: i) bacterial adhesion and aggregation, ii) growth and proliferation. The titanium with well-organized titania nanotube arrays is first modified by nitrogen dopants, then loaded with CuFeSe2 nanoparticles to form a p-n heterojunction. Such heterojunction can effectively separate the electrons and holes generated by CuFeSe2 under NIR excitation, where CuFeSe2 serves as an electron acceptor from adherent bacteria, thus disrupting the respiratory chain and eventually affecting the metabolism. Combined with the released ions in solution and photothermal effect, the formation of bacterial biofilm on the surface of titanium implants is prevented on both stages.

Peri-Implant Enhancement of the Breast: Imaging Features, Significance, and Management Strategies.

Peri-implant enhancement can be seen on contrast-enhanced breast MRI, but its association with malignancy has not been described, leading to considerable variability in assessment and recommendations by radiologists. This study evaluated imaging features, management, and outcomes of implant-related enhancement. This multisite IRB-approved retrospective review queried all breast MRI reports for keywords describing peri-implant enhancement, fluid, and/or masses (plus synonymous descriptions) and implant-associated malignancies, with subsequent imaging and chart review. Peri-implant enhancement and implant features were characterized. Assessments and outcomes were evaluated via clinical and imaging follow-up, aspiration/biopsy, and/or capsulectomy to evaluate for association of peri-implant enhancement with implant-related malignancy. A total of 100 patients had peri-implant enhancement. Uniform thin peripheral enhancement was most common (79/100, 79%). Capsulectomy was performed in 31/100 (31%), with benign capsular fibrosis/inflammation discovered in 26/31 (83.9%). Breast implant-associated anaplastic large cell lymphoma was present in 2/100 (2%), both with textured implants, while 98/100 (98%) had no implant-related malignancy. MRI recommendations varied: resume routine imaging (26/100, 26%), clinical management (18/100, 18%), follow-up MRI (17/100, 17%), MRI-directed US (17/100, 17%), aspiration/biopsy (11/100, 11%), and surgical consultation (10/100, 10%). Peri-implant enhancement is a nonspecific imaging finding with a low malignant association, especially when seen in isolation (no associated effusion, mass, or adenopathy). Implant surface texture should be considered in management recommendations; diagnostic capsulectomy is not recommended in patients with smooth implants. Additional studies are encouraged to validate nonoperative management recommendations.

Implant Surface Decontamination Methods That Can Impact Implant Wettability.

This review addresses the effects of various decontamination methods on the wettability of titanium and zirconia dental implants. Despite extensive research on surface wettability, there is still a significant gap in understanding how different decontamination techniques impact the inherent wettability of these surfaces. Although the literature presents inconsistent findings on the efficacy of decontamination methods such as lasers, air-polishing, UV light, and chemical treatments, the reviewed studies suggest that decontamination alters in vitro hydrophilicity. Post-decontamination surface chemistry must be carefully considered when selecting optimal surface treatments for implant materials. Further in vitro investigations are essential to determine which approaches best enhance surface wettability, potentially leading to improved implant-tissue interactions in clinical settings.

Molding Quality and Biological Evaluation of a Two-Stage Titanium Alloy Dental Implant Based on Combined 3D Printing and Subtracting Manufacturing.

Metal 3D printing has been used in the manufacturing of dental implants. Its technical advantages include high material utilization and the capacity to form arbitrarily complex structures. However, 3D printing alone is insufficient for manufacturing two-stage titanium implants due to the limited precision in printing titanium alloy parts. In this study, 3D printing was employed to create the implant structure, subsequently complemented by mechanical processing to refine the implant abutment connection and neck. Additionally, the mechanical properties of 3D-printed titanium alloy implants were evaluated through tensile and dynamic fatigue testing. The MTT assay was employed to assess the cytotoxicity of 3D-printed titanium alloy dental implants. The impact of bone union and osteogenesis from 3D-printed titanium alloy dental implants was investigated through in vivo experimentation. The results demonstrated that combining 3D printing with subsequent machining constitutes a viable method for the manufacture of two-stage titanium dental implants. Test results for mechanical properties indicated that heat-treated 3D-printed titanium alloy dental implants possess significant tensile strength and fatigue resistance and are capable of withstanding the robust chewing forces in the oral cavity. In vitro findings revealed that sandblasted and acid-etched 3D-printed titanium alloy exhibited negligible cytotoxicity, with osteoblast differentiation of hMSCs being more pronounced compared with the control group. In vivo studies indicated that no significant differences were observed in bone volume fraction, bone-implant contact rate, and unscrewing torque between 3D-printed titanium alloy dental implants and commercial SLA surface implants at both 1 and 3 months postimplantation.

Nitrogen-Doped Diamond-like Coatings for Long-Term Enhanced Cell Adhesion on Electrospun Poly(ε-caprolactone) Scaffold Surfaces.

Electrospun poly(ε-caprolactone) (PCL)-based scaffolds are widely used in tissue engineering. However, low cell adhesion remains the key drawback of PCL scaffolds. It is well known that nitrogen-doped diamond-like carbon (N-DLC) coatings deposited on the surface of various implants are able to enhance their biocompatibility and functional properties. Herein, we report the utilization of the pulsed vacuum arc deposition (PVAD) technique for the fabrication of thin N-DLC coatings on the surface of electrospun PCL scaffolds. The effect of N-DLC coating deposition under various nitrogen pressures on the morphological, mechanical, physico-chemical, and biological properties of PCL scaffolds was investigated. It was established that an increase in nitrogen pressure in the range from 5 × 10-3 to 5 × 10-1 Pa results in up to a 10-fold increase in the nitrogen content and a 2-fold increase in the roughness of the PCL fiber surface. These factors provided the conditions for the enhanced adhesion and proliferation of human mesenchymal stem cells (MMSCs) on the surface of the modified PCL scaffolds. Importantly, the preservation of N-DLC coating properties determines the shelf life of a coated medical device. The elemental composition, tensile strength, and surface human MMSC adhesion were studied immediately after fabrication and after 6 months of storage under normal conditions. The enhanced MMSC adhesion was preserved after 6 months of storage of the modified PCL-based scaffolds under normal conditions.

Polarization and Characterization of M1 and M2 Human Monocyte-Derived Macrophages on Implant Surfaces.

Foreign body reaction (FBR), an immune-mediated complex healing process, plays a crucial role in integrating implants into the body. Macrophages, as the first line of immune system interaction with implant surfaces, play a bidirectional role in modulating the inflammation-regeneration balance. For a deep understanding and the evaluation of the reactions between implant materials and immune responses, reliable in vitro methods and protocols are pivotal. Among different in vitro models, primary monocyte-derived macrophages (MDMs) present an excellent model for investigating macrophage-implant interactions. We have implemented an experimental protocol to evaluate the polarization of MDMs into M1 (classically activated) and M2 (alternatively activated) macrophages on implant surfaces. We isolated blood monocytes from healthy donors and differentiated them into macrophages using macrophage colony-stimulating factor (M-CSF). Differentiated macrophages were cultured on implant surfaces and polarized into M1 and M2 subtypes. M1 polarization was achieved in the presence of interferon (IFN)-γ and lipopolysaccharide (LPS), while M2 polarization was performed in a medium containing interleukin (IL)-4 and IL-13. We evaluated macrophage phenotypes by Enzyme-linkedImmunosorbent Assay (ELISA), confocal laser scanning microscopy (CLSM), and quantitative real-time PCR (qRT-PCR) based on panels of secreted cytokines, cell surface markers, and expressed genes. The extracted RNA was transformed into complementary DNA (cDNA), and qRT-PCR was used to quantify mRNA related to M1 and M2 macrophages. Accordingly, M1 macrophages have been characterized by higher expression of proinflammatory Tumor necrosis factor (TNF-α) cytokine and CCR7 surface marker compared to M2macrophages, which exhibited higher levels of CD209 and CCL13. Consequently, CCR7 and CD209 were identified as specific and reliable markers of M1 and M2 macrophage subtypes by immunostaining and visualizing by CLSM. Further confirmation was achieved by ELISA detecting elevated TNF-ɑ level in M1 and increased CCL13 in M2 cells. The proposed markers and experimental setup can be used effectively to assess the immunomodulatory potential of implants.

Osseointegration, inflammatory process and foreign body reaction of dental titanium implants

There has yet to be a consensus among researchers, professionals, companies, regulatory agencies, and technical standards regarding the definition of osseointegration. The divergence is conceptual and occurs due to explanations of the mechanisms of interactions among cells and proteins with the implant. In medicine, osseointegration is assessed visually in radiographic examinations by the absence of implant-bone space or by mechanical stability and absence of pain. In the medical field, it is mentioned that there is osseointegration of cemented orthopedic prostheses, stainless steel prostheses, Co-Cr-Mo alloys, and zirconia. In dentistry, osseointegration occurs only with titanium implants and is characterized by bonding bone cells with the implant surface through proteins. Titanium implants are chemically, physically, and mechanically linked to the bone through proteins adhered to their surface without a fibrous connective tissue interface. The protein-titanium connection has mechanical strength and can withstand functional loads on dental implants. Given the divergences in the understanding of osseointegration of titanium and zirconia implants, concepts are presented that explain the differences in biocompatibility and applications of biomaterials, inflammatory processes, osseointegration, foreign body reaction, and the mechanisms of protein interactions with surfaces of titanium and zirconia implants.

Biofilm and the effect of sonication in a chronic Staphylococcus epidermidis orthopedic in vivo implant infection model

BackgroundIn diagnosing chronic orthopedic implant infections culture of sonicate represents a supplement to tissue cultures. However, the extent to which biofilm forms on implant surfaces and the degree of dislodgement of bacteria by sonication remains unclear. In this in vivo study using a low bacterial inoculum, we aimed to determine whether a variable effect of sonication could be observed in a standardized in vivo model.Materials and MethodsSeven Wistar rats underwent surgery with intramuscular implantation of two bone xenograft implants, each containing two steel plates. The grafts were inoculated with approximately 500 colony forming units (CFU) of Staphylococcus epidermidis ATCC 35984. After 20 days the rats were sacrificed, and the steel plates were removed from the bone grafts. Epifluorescence microscopy and scanning electron microscopy (SEM) were used to visualize biofilm formation and dislodgement on the plate surfaces. In addition to cultures of sonicate, a quantitative S. epidermidis specific PCR was developed for enumeration of bacteria.ResultsA chronic, low-grade implant infection was successfully established, with all animals remaining in good health. All infected bone graft implants yielded abundant growth of S. epidermidis, with a median of 3.25 (1.6–4.6) × 10⁷ CFU per/graft. We were unable to distinguish infected plates from negative controls using epifluorescence microscopy. On infected plates small colonies of staphylococci were identified by SEM. The number of bacteria detected in the sonicate was low with 500 (100–2400) CFU/plate and 475 (140–1821) copies/plate by qPCR. The difference in area covered by fluorescent material before and after sonication was 10.1 (5.7–12.3) %, p = 0.018.ConclusionDespite the pronounced infection in the surrounding tissue, only few bacteria were detected on the surface of the steel implants. This is evident from the minimal findings by SEM before sonication, as well as the very low CFU counts and DNA copies in the sonicate. Sonication did not show variable effectiveness, indicating it is a valuable addition to, but not a replacement for biopsy cultures in cases of implant-associated infections with low-virulence microorganisms.

Surface Modification of Anodized Titanium Surfaces with Chitosan/ε-Polylysine Coating, Aiming for an Improved Bioactivity, Biocompatibility, and Anti-Bacterial Properties for Orthopedic Applications

The increasidng demand for implants due to the aging populations highlights the necessity for applying highly functional coatings on the surface of implants. This study investigates the implications of applying a chitosan/polylysine composite coating on anodized titanium surfaces, aiming for improved biocompatibility, bioactivity, and anti-bacterial properties. Titanium substrates were anodized at 40 volts for a duration of two hours, followed by dip coating with the chitosan/polylysine composite. Fourier-transform infrared (FTIR) analysis was employed to characterize the polymer structure, while field emission scanning electron microscopy (FESEM) and energy-dispersive X-ray spectroscopy (EDS) techniques were utilized to evaluate nanotube morphology and the coating structure. Results showed that samples containing 1.5% polylysine exhibited noticeable anti-bacterial properties and cell viability above fifty percent. Subsequent immersion in simulated body fluid (SBF) for a duration of two weeks revealed the formation of apatite crystals on the coated samples, indicating that the samples are bioactive. Furthermore, polylysine contributed to enhanced resistance against degradation in phosphate-buffered saline (PBS) solution. Overall, the chitosan/polylysine composite coating exhibited promising mechanical and biomedical characteristics, suggesting its potential for applications in orthopedic implants.

Optimization of 3D-titanium interbody cage design. Part 1: in vitro biomechanical study of subsidence.

Cage subsidence is a complication of interbody fusion associated with poor clinical outcomes. 3D-printed titanium interbody cages allow for the alteration of features such as stiffness and porosity. However, the influence of these features on subsidence and their biological effects on fusion have not been rigorously evaluated. This 2-part study sought to determine how changes in 3D-printed titanium cage parameters affect subsidence using an in vitro bone model (Part 1) and biological fusion using an in vivo sheep model (Part 2). Biomechanical foam block model. In Part 1 of this study, 9 implant types were tested (8 per implant type). The implant types included 7 3D-printed titanium interbody cages with various surface areas, porosities, and surface topographies, along with 1 standard polyetherether ketone (PEEK) cage and 1 solid titanium cage. Subsidence testing was performed in a standardized foam block model using 2 different densities of foam. Digital imaging correlation was used to determine the relative vertical displacement of the interbody cage-foam block construct. Subsidence decreased as the surface contact area with the bone model increased (all p≤0.01). Increased porous surface topography increased subsidence, while a nonporous surface significantly decreased subsidence (all p<0.001). Subsidence did not differ based on changes in implant porosity (all p≥0.35) or material property/modulus (all p≥0.19). Subsidence was significantly decreased with the higher density foam (p<0.001). The stiffness of the implant was affected by porosity (all p<0.02) and smooth surface topography (p=0.01) but not by lumen size (all p≥0.15). Stiffness did not differ between porous titanium and PEEK implants (p=0.96), which were both less stiff than solid titanium implants (both p <0.001). Surface area negatively correlated with subsidence (r=-0.786, p=0.012) but was not correlated with stiffness (r=0.560, p=0.12). Implant surface area and surface topography greatly influenced interbody subsidence. Apparent stiffness, implant porosity, and material property did not affect subsidence in this in vitro model. Higher foam density also led to lower subsidence than low-density foam. Biological response in the in vivo setting likely also influences clinical subsidence, which is evaluated in the companion study (Part 2). This study provides valuable information regarding the new 3D-printed titanium technology. We showed that cage surface area and surface topography were the implant design parameters that had the greatest influence on the development of interbody subsidence. Moreover, bone mineral density was the factor that had the greatest effect on subsidence prevention. These data support patient optimization before surgery and emphasize the importance of endplate protection during surgery.

Survival Rates and Risk Factors of Resorbable Blast Media Surface Dental Implants: A Retrospective Cohort Study with an Average 60-Month Follow-Up.

This retrospective cohort study aimed to evaluate the survival rates and risk factors associated with Resorbable Blast Media (RBM) surface dental implants. The study involved 1,130 implants placed in 260 patients, with a follow-up ranging from a minimum of 26 months to a maximum of 120 months, for an average of 60 months. 1,130 RBM surface implants with hybrid macro-geometry were placed in 260 patients. Implant survival and failure rates were analyzed over an average 60-month follow-up. Failure rates were examined based on implant length, patient gender, and sinus lift procedures. Additional factors, including patient age, implant placement timing (immediate vs. delayed), guided bone regeneration (GBR), implant diameter, and implant location, were assessed to determine their impact on long-term implant success. The overall survival rate for the implants was 94.4%, with most failures occurring within the first 12 months postplacement. Male patients experienced significantly higher failure rates (7.36%) than female patients (4.0%). Short implants (8 mm) were particularly vulnerable to failure, with an 8.65% failure rate. Sinus augmentation procedures also presented an increased risk, with 10% failure for lateral sinus augmentation and 9.78% for crestal sinus elevation. In contrast, factors such as patient age, timing of implant placement, GBR, implant diameter, and implant location did not significantly influence failure rates. Notably, narrow-diameter implants (3.3 and 3.7 mm; n=97) in the molar region did not increase the risk of failure, with only 5 experiencing failure. Failures post-prosthetic loading were most common after about 3 years. This study confirms the long-term viability of RBM surface implants, with high survival rates when early failures are mitigated. Short implants and sinus lift procedures pose greater risks of failure, particularly in the early stages. However, simultaneous GBR and sinus procedures did not significantly impact long-term outcomes, affirming the safety and efficacy of these complex interventions.

Reduction of Streptococcus salivarius by Chlorella-Mediated Antimicrobial Photodynamic Therapy.

Introduction: Nowadays, antimicrobial photodynamic therapy (aPDT) has been introduced as one of the minimally invasive methods for disinfection of the surfaces of dental implants. Being derived from seaweed, Chlorella has been used as a photosensitizer in this study. This study aimed to investigate the impacts of aPDT with Chlorella on the rate of reduction of Streptococcus salivarius in vitro. Methods: The minimum inhibitory concentration of Chlorella, the sublethal exposure to 660 nm diode laser irradiation, and the minimum sublethal dose of aPDT utilizing Chlorella against S. salivarius were determined. Finally, the CFU/mL value of each plate was calculated. Then, Tukey HSD and one-way ANOVA tests were utilized for comparison the number of colonies after the interventions. Results: A concentration of 250 µg/mL of Chlorella at an irradiation time of 3 minutes, was identified as a sublethal dose of aPDT for the reduction of S. salivarius. In contrast, the application of aPDT utilizing a 660 nm diode laser for 4 minutes in combination with Chlorella at a final concentration of 500 µg/mL, demonstrated significantly greater efficacy in reducing S. salivarius compared to the other experimental groups (P<0.001). Conclusion: Chlorella 500 µg/mL mediated aPDT (660 nm, 4 minutes) has a significant effect on reducing S. salivarius count.

Impact of Bulk Nanobubble Water on a TiO2 Solid Surface: A Case Study for Medical Implants.

In the field of medical implants, enhancing the wettability of artificial surfaces is crucial for improving biocompatibility. This study investigates the potential of ozone nanobubble water, an aqueous solution known for its strong oxidizing and sterilizing properties, to modify the surface of titanium dental implants. By immersing the implants in ozone nanobubble water for ∼10 min, we observed a significant transformation of their surface characteristics. Implant surfaces that had become hydrophobic over time, likely due to organic contaminants, became superhydrophilic, exhibiting a contact angle near zero. Fresh implant material is initially hydrophilic but becomes hydrophobic within a few days of drying. In sharp contrast, the hydrophilicity induced by ozone nanobubble water treatment persisted for more than one month. This durability suggests not only the removal of organic matter through cleaning but also a substantial alteration in the surface properties of the implants. The generation of ozone nanobubble water involved releasing ozone microbubbles into an aqueous solution containing trace amounts of iron and manganese, resulting in spherical particles with an average diameter of ∼10 nm. These particles could be bulk nanobubbles, a stabilized gas body surrounded by a solid shell composed of iron hydroxide. Termed "nanoshells" in our previous study, these particles demonstrated exceptional dispersibility without the need for stabilizing agents such as surfactants or capping agents, attributed to their inherent high wettability. The sustained hydrophilicity of the implant surfaces might be attributed to the adherence of these hydrophilic nanoshells to the implant's surface. This study highlights the potential of ozone nanobubble water for long-term surface modification of dental implants, offering a promising avenue for enhancing implant biocompatibility.

The Effect of NiTi Brush, Polishing Brush, and Chemical Agent on the Dental Implant Surface Morphology and Cytocompatibility.

To invitro investigate the effect of different implant surface decontamination methods and treatment storing conditions on implant surface morphology and cell viability. Titanium disks with a sand-blasted and acid-etched surface (Promote, PRO) were treated with diamond polishing brushes (BRUSH), nickel-titanium brushes (NITI), or phenol and sulfuric acid-gel (GEL). The disks were stored in saline (-S) or left exposed to air overnight (-A). Untreated (PRO) and machined (MACHINED) disks were used as controls. GEL samples were treated for the 60 s, while the operative time was recorded for BRUSH and NITI. The samples were subjected to scanning electron microscopy (SEM), surface roughness measurements, and cell viability (SaOS-2 cells, 7 days) assessment. The operative time was shorter for NITI than for BRUSH (p = 0.017). The original surface morphology (PRO) was not altered in the GEL group, in contrast with what was observed for BRUSH and NITI. The type of storage did not influence the surface morphology. No significant differences in Sa and Sz were observed among the groups, except for MACHINED, which presented lower Sa values (p < 0.05). Cells were able to proliferate on all surfaces. NITI-S showed significantly higher cell viability compared to all groups (p ≤ 0.001), except for NITI-A and MACHINED. Among the treated groups, only one additional significant difference was found, as NITI-A performed better than GEL-S. None of the investigated protocols compromised the cytocompatibility of the titanium dental implant surface. The best results were registered in the NITI group when the samples were stored in saline. Future studies should confirm the effectiveness of the proposed methods in removing bacterial biofilm from contaminated implant surfaces.

Tailoring magnesium-doped coatings for improving surface and biological properties of titanium-based dental implants

Physicochemical modifications of biomaterials have been proposed to overcome bone integration impairment and microbial infections. The magnesium (Mg) incorporation on dental implant surfaces has shown positive results in bone-to-implant contact and in the reduction of microbial colonization. Here, we explored the potential of using different Mg precursors to synthesize coatings via plasma electrolytic oxidation (PEO) on commercially pure titanium (cpTi), aiming to optimize the surface and biological properties. For this, we investigated Mg acetate and Mg nitrate precursors in different concentrations (0.04 M and 0.12 M), using calcium (Ca) and phosphorus (P) as the base electrolyte for all groups. Coatings with only the CaP base electrolyte were used as the control group. The surfaces were characterized by confocal laser scanning microscopy, scanning electron microscopy, film thickness measurement, profilometry, wettability, X-ray diffraction, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, electrochemical behavior, and ion release. For biological analyses, the adhesion (2 h) of Streptococcus sanguinis was evaluated, as well as MC3T3-E1 osteoblastic cells proliferation at 1 and 3 days, and mineralization of calcium phosphates after 28 days. PEO treatment using different Mg precursors promoted physicochemical modifications of cpTi. The experimental groups MgN 0.04 and MgN 0.12 exhibited higher surface roughness and wettability compared to the other surfaces. Regardless of the Mg precursor, the higher the ion concentration in the electrolyte solution, the higher the Mg atomic concentration on the surfaces. Concerning the electrochemical behavior, the results indicated that the incorporation of Mg in the coatings may enhance the electrochemical performance. Mg treated surfaces did not promote greater bacterial adherence when compared to the control. MgAc 0.04 and MgAc 0.12 coatings displayed improved MC3T3-E1 pre-osteoblastic cells proliferation at day 3 compared to other groups. The hydroxyapatite formation on MgAc 0.12 surfaces was higher than in the other groups. Our data indicate that Mg precursor selection positively influences physicochemical and biological properties of coatings. Specifically, MgAc 0.12 surfaces showed the most promising surface features with greater cell proliferation, without affecting microbial colonization, being an excellent candidate for surface treatment of titanium-based dental implants.

Study of Physicochemical and Biological Properties of UHMWPE Joint Implant With Ti, Ta, and Zr Thin Films

ABSTRACTThis study aimed to improve the surface of polymer implants by examining the physicochemical and biological properties of UHMWPE coated with titanium, tantalum, and zirconium thin films. The coatings exhibited enhancements in wettability alongside diminished roughness. The Zr film exhibited a contact angle of 16°, a significant improvement compared to the UHMWPE sample, which has an angle of 102°. Moreover, the roughness of the pristine sample (0.958 μm) was substantially reduced to 0.403 μm with the Ta film. These characteristics prevented the adhesion of fibroblasts, minimizing the risk of fibrous encapsulation surrounding the implant [2]. Micro‐abrasion tests demonstrated that the coatings reduced the wear coefficient, making them ideal for increasing the longevity of the implant in the human body. Transitioning from a wear coefficient of 0.47 × 10–12 m2/N for UHMWPE, values as low as 0.21 × 10–12 m2/N were attained, particularly in the sample with the Ti film. Therefore, the coatings exhibit favorable characteristics for the intended biomedical application.